DRAFT TANZANIA STANDARD          TDC 11  CD 2 (1945) 
                                                                                                                        First Edition                                           
©TBS 2023 All right reserved                                                                      First edition 2023 
  
Leather  - Volleyball  — Specification  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
TANZANIA BUREAU OF STANDARDS  
  
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©TBS 2018 All right reserved                                                                      First  edition 2023 
              TDC 11 CD 2 (1945 ) 
Foreword  
This Draft Tanzania Standard is being developed by the Leather and Leather Products  Technical 
Committee under supervision of the Textile and Leather Division Standards Committee and it is in 
accordance with the procedures of the Bureau.  
 This Tanzania Standard has been prepared with assistance drawn from:  
 . 
     IS 4191 , Specification for leather for volleyball  
  
  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
 1 Scope  
This Draft Tanzania Standard specifies  the requirements and test methods for volleyball made from 
leather  or synthetic materials . 
2 Normative Reference s  
The following referenced document is indispensable for the application of this standard . 
TZS 4 Rounding of numerical values.  
3 Terms and definitions  
For the purposes of this standard, the following definitions shall apply.  
3.1 p olyurethane (pu) coated leather  
leather with a coating of polyurethane  
3.2 p olyvinyl chloride ( pvc) coated  textiles  
textiles with a coating o f polyvinylchloride  
3.3 synthetic materials  
materials made of PU, PVC and other synthetic materials which are used as natural leather substitute  
4 Requirements  
4.1 General Requirements  
The method of construction shall follow the principle applicable for that type of ball.   
4.1.1  Material requirements  
Volley balls may be made of stitched leather, stitched synthetic material or moulded material that shall 
comply with the requirements given in Table 1.  
4.1.2  Finish   
volleyball shall have a smooth surface finish.  
4.1.3  Shape, dimensions a nd mass    
Shape, dimensions and mass for volleyball shall be as given in Table 1.  
 
Table 1  — Material characteristics and specific requirements for  volleyball  
SN  Characteristic  Materials and requirements  Test 
method   size 5 -
indoor  size 5  - 
school 
volleyball   size 5 - 
kids 
Volleyball  Size 4 – 
Indoor 
Volleyball  Official 
size 
1 Mass, g  260-280 195-225 160-180 240-260 260-280 Annex A  
2 Circumference, mm  650-670 650-670 645-665 620-640 660-680 Annex B  
3 Sphericity,%, Max.  1.5 2 2 2 1.5 Annex B  
4 Loss of pressure, max.  20 25 25 25 20 Annex C  
5 Water absorption test  
a) Average water uptake 
of the initial mass of the tested 
balls, %, max.  
 
b) Water uptake per 
ball, %, max.  
  
10 
 
 
 
15  
15 
 
 
 
20  
15 
 
 
 
20  
15 
 
 
 
20  
10 
 
 
 
15  
 
Annex D   
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
 6 Rebound at 20 °C,  
cm 
 120 – 165 120 – 165 110 – 160 110 – 160 120 – 
165 Annex E  
7 Rebound at 5 °C, cm, min.  
 120 120 120 110 120 Annex E  
8 Difference between lowest and 
highest rebound per ball 
tested, mm, max.  10 10 10 10 10 Annex E  
9 
 
 
 
 Shape and size retention test, including change of pressure (after 2 000 kicks)  
 
a) Damage to seams and air 
valve  None  
 None  
 None  
 None  None  
  
 
 
Annex  F b) Increase in circumference, 
mm, max.  1.5 
 1.5 
 1.5 
 1.5 1.5 
 
c) Deviation on sphericity  
 1.5 
 1.5 
 1.5 
 1.5 1.5 
 
 
d)Change of pressure, bar, 
max.   
0.1 
  
0.1 
  
0.1 
  
0.1  
0.1 
 
 
 
5 Marking  
5.1 Each ball shall be legibly and indelibly marked with the following;  
  
a) Name of the material;  
b) Manufacturer’s name , address  and/or registered trade mark;  
c) Month and year of manufacture;  
d) Size of volleyball  
e) Country of manufacture or country of origin; and  
f) Batch number.  
5.2  Each bale shall be legibly and indelibly marked with the following information:  
  
a) Name of product;  
b) Number of balls;  
c) Name of manufacturer or local supplier’s name and/or registered trade mark; and  
d) Country of manufacture or country of origin.  
  
 
 
 
 
 
 
 
  
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
 Annex A  
(normative)  
 
Determination of weight  
 
A.1 Principle  
The weight of balls is very important to ensure consistence for the wind resistant.  
 
A.2 Apparatus  
An electronic balance, capable of measuring to the nearest 0.01 g.  
 
A.3 Procedure  
Select 3 pre -conditioned balls. Weigh them in an enclosed chamber to avoid wind flow. 
Record the mass to the nearest 0.01 g.  
 
A.4 Results  
Record the average mass of the three balls.  
 
 
 
  
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
 Annex B  
(normative)  
 
Determination of circumference and sphericity  
 
 
B.1 Principle  
The circumference test indicates the dimension of the ball as an average value measured 
from different axes. This test is critical to ensure the ball is the correct size for the game of 
volleyball . 
 
B.2 Apparatus  
Equipment capable of measuring circumferenc e and sphericity (roundness) of volleyballs  
(see Figure B.1).  
 
The equipment may be automated and connected to a PC monitor with measuring software 
capable of taking several radii of a ball and giving an average measurement of the 
circumference and spheric ity or any other suitable equipment.  
 
 B.3  Expression of results  
The results will be read off the monitor for automatic equipment or any other suitable 
equipment display.  
  
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
KEY 
a) Ball 
b) Grippers  
c) Tangential arms  
d) Pressure pipe  
e) Rotating arm  
f) Control panel with  display screen  
 
Figure B.1 — A typical equipment for circumference and sphericity  
Formula for sphericity  
Insert,,,,,,,,,,,,,,,,,,,,,,,,,  
 
 
a b
c
d
e
f 
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
 Annex C  
(normative)  
 
Determination of loss of pressure  
 
C.1Principle  
This test measures the difference in pressure over time. The aim is to ensure that the ball 
does not deflate too quickly, even when not used.  
 
C.2 Apparatus  
A calibrated pressure gauge, capable of measuring 1.5 bar and an accuracy of ± 0.01 bar.  
 
C.3 Procedure  
C.3.1   Condition 3 volleyball samples for at least 24 h r in a standard atmosphere of 
temperature 20 °C ± 2 °C and relative humidity 65% ± 5%.  
C 3.2   Measure the pressure in the balls to ensure that they comply with the recommended 
pressure before the test.  
C.3.3   Keep the samples in the same standard atmosphere of temperature 20°C ± 2°C and 
relative humidity 65% ± 5% for 72 h r. 
C 3.4   After this period, measure the pressure in the samples and note the difference.  
C.4 Results  
Calculate the pressure difference and report to the nearest 0.01 bar.  
 
 
   
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
Annex D  
(normative)  
 
Determination of water absorption  
 
 
D.1 Principle  
 
The volleyball is placed in container filled with water. The ball is then compressed into the 
water by appropriate means and left to soak in the water. The ball is then weighed again 
after 250 compression cycles and compared to the original weight.  
 
D.2 Apparatus  
 
Equip ment capable of turning the volleyball in various directions between the compressions 
thus, the complete volleyball comes in contact with the water during the test (see Figure 
D.1).  
 
 
 
Figure D.1 — A typical water absorption equipment  
 
 
 
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
 
 
D.3 Results  
 
Calculate the weight difference between the initial and final weight  
 
11 2 100
MMMY
 
Where  
 
M1  is the  initial weight of the sample;  
 
M2  is the weight after water absorption; and  
 
Y    is the % weight gain (amount of water absorbed).  
 
   
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
Annex E  
(normative)  
 
Determination of ball rebound  
E.1 Principle  
 
The sample ball is dropped in a guided free fall with a defined velocity on to a fixed plate. 
The ball hits the surface at specific points in the middle of the panels, distributed over the 
surface of the ball. T he panels will be selected such that the number of testing points is 
evenly distributed on the different panel shapes.  
 
E.2 Apparatus  
 
 Equipment capable of allowing for the ball to free fall vertically from a height of 2.00 m ± 
0.01 m (measured from the bottom of the ball) without imparting any impulse of spin. The 
surface that the ball is to rebound on shall be metal for outdoor and bea ch soccer balls (see 
Figure E.1).  
 
E.3 Results  
 
The ball rebound height of any tested sample is the mean of 10 from the 10 performed from 
each ball in ambient conditions. The mean value of each of the three samples must fall 
within the requirements. In add ition, the difference between the highest and lowest means 
shall be compared and shall also fall within the respective requirement.  
   
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
 
KEY 
 
a) Vertical scale  
b) Ball 
c) Guidance system  
d) Ring 
e) Video camera  
f) Connecting cables  
g) Control panel complete with switches  
h) Display screen  
i) Digital recording system  
j) Sensor (for determining time of impact)  
k) Metal surface  
 
 
Figure E.1 — A typical vollyball  rebound test equipment  
 
  
 
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
Annex F  
(normative)  
 
Determination of shape and size retention  
 
 
F.1 Principle  
 
The ball is repeatedly shot against a metal surface automatically (or otherwise stated) before 
being returned into the shooting device. The number of cycles simulates use over a period of 
time. The worn samples can then be re -checked for size, weight and shape in orde r to 
ensure they do not change significantly with use.  
 
F.2 Apparatus  
 
Equipment capable repeatedly throwing a ball (2000 times) against a specified surface 
automatically or otherwise stated (see Figure F.1).  
 
 
 
Figure F.1 — A typical Device for throwing balls  
 
 
 
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©TBS 2018 All right reserved                                                                      First  edition 2023 
  
F.3 Calculation and expression of results  
 
The results from the tests performed after the 2000 cycles are noted as follows:  
 
a) Initial pressure of the samples (before shooting) minus pressure after shooting gives  
 
b) Pressure loss expressed in bar with  2 decimal places; example -0.02 bar.  
 
c) Visual inspection of any damage.  
 
d) Change in circumference results as per the  prescribed test method.  
 
e) Change in sphericity results as per the prescribed test method.  
 
The values of circumference, sphericity and pressure are compared to the values from the 
previous tests. The difference between the value obtained after the shooter test and prior to 
the test, is denoted as an  an absolute increase/decrease for circumference and pressure 
and a percentage .